Commentary: How could the Supreme Court change gun laws? By ending gerrymandering.

By Mark Kaplan and Adam Winkler

Special to The Washington Post

Congress has shown no sign of changing any gun laws, more than four weeks after the horrific mass shooting in Las Vegas. With nearly seven in 10 Americans saying Congress “needs to do more” to reduce gun violence, people are frustrated by the lack of movement on meaningful reform. But a major case pending before the Supreme Court could break the logjam — even though the case has nothing to do with the Second Amendment.

The justices recently heard arguments in an important case about the constitutionality of partisan gerrymandering. In states like North Carolina and Wisconsin, where the population is evenly split between the two parties, the legislatures drew election districts to strongly favor the GOP, locking in at least a 60 percent majority of seats. Democrats have done it, too, in places like Oregon and Maryland.

The justices are being asked to decide if this practice of manipulating district lines to guarantee one party a disproportionate number of seats unconstitutionally dilutes the other party’s supporters’ right to vote. If the court agrees, it could have a broad impact on American politics — and one of the biggest effects could be on guns. Partisan gerrymandering is one of the main reasons Congress has not enacted any significant new gun laws in recent years.

As gerrymandering has been more successful in Republican-controlled legislatures, Congress today has a disproportionate number of Republican representatives. In November, Republican congressional candidates won 49.9 percent of the vote while securing 55.2 percent of House seats. Democrats, by contrast, won 47.3 percent of the vote and only 44.8 percent of seats.

Not only has partisan gerrymandering skewed representation in Congress toward the party opposed to gun safety legislation, it has also resulted in the election of more extreme candidates from both parties. Because partisan gerrymandering makes the general election all but meaningless, the only race that really matters is the primary. Voters in primaries, however, tend to be more ideologically “pure” and less open to compromise.

People often say the National Rifle Association is so powerful because it buys off politicians. The NRA certainly does spend considerable amounts on campaigns — especially independent expenditures, or money that does not go directly to candidates. The group spent a whopping $5.6 million to defeat Democrat Deborah Ross in the 2016 North Carolina Senate race, according to the Center for Responsive Politics, the most spent on a single congressional candidate in the 2016 cycle.

Much of the NRA’s strength, however, comes from partisan gerrymandering. Through its endorsements, the NRA is able to swing the intense, single-issue, pro-gun voters who vote in large numbers in Republican primaries. As a result, candidates fear supporting even minimal gun safety reform for fear of losing the NRA’s support and being “primaried” by a more ideologically rigid candidate backed by the nation’s leading gun rights group.

Although there is no pro-reform organization with the political pull of the NRA, partisan gerrymandering may also push Democrats away from compromise on guns. Gun control has become increasingly important to many of the party’s voters in recent years, with 85 percent of Democrats supporting stricter gun legislation. This, too, may mean that Democratic candidates with more moderate positions on guns are less likely to succeed in their primaries.

The result is that the ideological divide between the Republican and Democratic caucuses in Congress over guns has never been greater. Even broadly popular reforms such as universal background checks and a no-buy list for suspected terrorists, measures that are supported by more than 75 percent of Americans, seemingly have no chance of being enacted.

Polls consistently show that Americans are in the middle on guns. Like the NRA, the public broadly tends to favor the right of individuals to have guns for personal protection. Like Everytown for Gun Safety, one of the main gun safety groups, voters also favor targeted reforms to make it harder for the most dangerous people to obtain the most dangerous guns. That spirit of moderation, however, is woefully underrepresented in our gerrymandered Congress.

Partisan gerrymandering is not just a matter of one party discriminating against the other or locking in its own candidates. It also exaggerates the effects of an already deeply polarized electorate and makes the type of give-and-take bargaining necessary for effective lawmaking more difficult. When it comes to guns, gerrymandering also has significant public health consequences, making it that much harder to reduce the more than 100,000 people killed and injured by firearms each year.

In the wake of Las Vegas and other recent mass shootings, nothing in federal law has changed. Reforms that could reduce the daily toll from gun violence, such as universal background checks, remain mere proposals with no chance of passage. But if the Supreme Court rules that partisan gerrymandering violates the Constitution, we may see less extreme candidates elected to Congress — and maybe we will finally break the logjam on guns.

— Mark Kaplan is a professor of social welfare at the UCLA Luskin School of Public Affairs, specializing in firearm violence as a public health problem. Adam Winkler is a professor at UCLA School of Law and the author of “Gunfight: The Battle over the Right to Bear Arms in America.”